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101.
A double fiber-optic Mach-Zehnder interferometer for sensing magnetic fields is devised using two polarization maintaining single-mode fibers. This sensor achieves not only highly sensitive performance but also excellent immunity from temperature disturbance. The sensitivity attains 243 deg/mT (mT=10-3N/A) for the sensing part of the 5 cm long fiber.  相似文献   
102.
This paper describes a double fiber-coiled interferometric deformation sensor fabricated using paired polarization maintaining single-mode fibers. A change in bending-induced birefringence plays a fundamental role in the sensor performance as the fiber-coil is being deformed across its cross-section. Differential optical heterodyne detection processes allow us to implement two-mode operations; one is widely dynamic operation and the other highly sensitive operation around a target region. The deformation sensitivity for one-turn fiber-coil is 2.5 deg/mm for the widely dynamic operation, whereas 9.5X10 deg/mm for the highly sensitive operation. The double fiber-coiled deformation sensor can eliminate external, undesirable temperature disturbances.  相似文献   
103.
A simple model is presented for the πN scattering in the P11 channel from the threshold to the Roper resonance N(1470). The model starts with the πBB′ coupling of the Yukawa type where B (and B') stands for N, R or Δ. A unitarized scattering amplitude is constructed from the K-matrix which is obtained perturbatively. With appropriate coupling constants and form factors for the πBB′ interactions, which conform to the quark model, the P11 scattering can be well reproduced. It is emphasized that the process πN → ππΔπN, which has been ignored hitherto, plays a crucial role in the energy region considered.  相似文献   
104.
The experimental result of the orbital and spin moments for Co in YCo5 is analyzed by the use of the approximate d bands for YCo5. The calculation of the anistropy constants Ku1 and Ku2 is worked out. Finally, the contributions to the anistropy constants due to 3d bands of CoI, those of CoII, those of CoI and CoII, and 3d and 4d bands of CoI, CoII and Y are discussed.  相似文献   
105.
One-dimensional displacements of a moving body are dectected from the phase-modulated beat signal of light, generated by two successive ultrasonic modulators. Measurements of triangular and random displacements are demonstrated using a movable reflection mirror. For a sinusoidal motion its amplitude is measured down to 2.2 Å.  相似文献   
106.
107.
LISICON thin films have been prepared with RF sputtering and subsequent heat-treatment. The crystal phases of sputtered films depend on the sputtering conditions, especially the target composition and ambient gas atmosphere. Though the as-sputtered films in Ar-O2 mixed gas (target composition: Li3Zn0.5GeO4+0.5 ZnO, gas pressure: 9×10-2 Torr, oxygen gas content: 74.6%) were amorphous; LISICON single phase thin films were obtained after annealing at 600°C for 6 h. The conductivity of the film at 500°C is 5×10-3ω-1cm-1 which is slightly lower than that for ceramic Li3Zn0.5GeO4.  相似文献   
108.
The complex degree of coherence over a telescope aperture is measured by processing instantaneous values of the complex degree of coherence fluctuated by turbulent atmosphere. Fringe patterns produced by a computer-controlled wave-front folding interferometer are analyzed in a short time by a photodiode array to calculate the instantaneous values of the complex degree of coherence. The system is applied to one-dimensional simulation experiments.  相似文献   
109.
Summary Asymptotic properties of several estimators of interclass correlation from familial data are examined in the case of a variable number of siblings per family. After showing that the usual sib-mean estimator is not consistent, a modified sib-mean estimator is proposed. Asymptotic distributions of estimators are derived and a test procedure is provided for a certain testing problem concerning interclass correlation. Several estimators are compared in the various mean number of siblings per family, using asymptotic mean square errors. The Institute of Statistical Mathematics  相似文献   
110.
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